From: email@example.com (David Megginson)
Subject: Mach/Minix/Linux/Gnu etc.
Date: 1 Feb 92 17:11:03 GMT
Organization: University of Toronto - EPAS
Well, this has been a fun discussion. I am absolutely convinced by
Prof. Tanenbaum that a micro-kernel _is_ the way to go, but the more
I look at the Minix source, the less I believe that it is a
micro-kernel. I would probably not bother porting Linux to the
M68000, but I want more services than Minix can offer.
What about a micro-kernel which is message/syscall compatible with
MACH? It doesn't actually have to do everything that MACH does, like
virtual memory paging -- it just has to _look_ like MACH from the
outside, to fool programs like the future Gnu Unix-emulator, BSD, etc.
This would extend the useful lives of our M68000- or 80286-based
machines for a little longer. In the meantime, I will probably stay
with Minix for my ST rather than switching back to MiNT -- after all,
Minix at least looks like Unix, while MiNT looks like TOS trying to
look like Unix (it has to, to be TOS compatible).
From: firstname.lastname@example.org (peter da silva)
Subject: What good does this war do? (Re: LINUX is obsolete)
Date: 3 Feb 92 16:37:24 GMT
Organization: Xenix Support, FICC
Will you quit flaming each other?
I mean, linux is designed to provide a reasonably high performance environment
on a hardware platform crippled by years of backwards-compatible kludges. Minix
is designed as a teaching tool. Neither is that good at doing the other's job,
and why should they? The fact that Minix runs out of steam quickly (and it
does) isn't a problem in its chosen mileau. It's sure better than the TOY
operating system. The fact that Linux isn't transportable beyond the 386/AT
platform isn't a problem when there are millions of them out there (and quite
cheap: you can get a 386/SX for well under $1000).
A monolithic kernel is easy enough to build that it's worth doing it if it gets
a system out the door early. Think of it as a performance hack for programmer
time. The API is portable. You can replace the kernel with a microkernel
design (and MINIX isn't the be-all and end-all of microkernel designs either:
even for low end PCs... look at AmigaOS) without disturbing the applications.
That's the whole point of a portable API in the first place.
Microkernels are definitely a better design for many tasks. I takes more
work to make them efficient, so a simpler design that doesn't take advantage
of the microkernel in any real way is worth doing for pedagogical reasons.
Think of it as a performance hack for student time. The design is still good
and when you can get an API to the microkernel interface you can get VERY
impressive performance (thousands of context switches per second on an 8